§ 90. The _teleological_ proof argues that the world can owe its origin only to an _intelligent first cause_. The evidence for this is furnished by the cunning contrivances and beneficent adaptations of nature. These could not have come about through chance or the working of mechanical forces, but only through the foresight of a rational will. This argument originally infers God from the character of nature and history; and the extension of mechanical principles to organic and social phenomena, especially as stimulated by Darwin's principle of natural selection, has tended greatly to diminish its importance. When, on the other hand, for nature and history there are substituted the intellectual and moral activities themselves, and the inference is made to the ideal which they imply, the teleological argument merges into the ontological. But the old-fashioned statement of it remains in the form of religious faith, and in this capacity it has had the approval even of Hume and Kant, the philosophers who have contributed most forcibly to its overthrow as a demonstration of God. They agree that the _acknowledgment_ of God in nature and history is the sequel to a theistic belief, and an inevitable attitude on the part of the religious consciousness. [Sidenote: God and the World. Theism and Pantheism.] § 91. Another group of ideas belonging to philosophical theology consists of three generalizations respecting God's relation to the world, known as _theism_, _pantheism_, and _deism_. Although, theoretically, these are corollaries of the different arguments for God, two of them, theism and pantheism, owe their importance to their rivalry as religious tendencies. _Theism_ emphasizes that attitude to God which recognizes in him an historical personage, in some sense distinct from both the world and man, which are his works and yet stand in an external relationship to him. It expresses the spirit of ethical and monotheistic religion, and is therefore the natural belief of the Christian. _Pantheism_ appears in primitive religion as an animistic or polytheistic sense of the presence of a divine principle diffused throughout nature. But it figures most notably in the history of religions, in the highly reflective Brahmanism of India. In sharp opposition to Christianity, this religion preaches the indivisible unity of the world and the illusoriness of the individual's sense of his own independent reality. In spite of the fact that such a doctrine is alien to the spirit of Christianity, it enters into Christian theology through the influence of philosophy. The theoretical idea of God tends, as we have seen, to the identification of him with the world as its most real principle. Or it bestows upon him a nature so logical and formal, and so far removed from the characters of humanity, as to forbid his entering into personal or social relations. Such reflections concerning God find their religious expression in a mystical sense of unity, which has in